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By Z. Luo, China University of Mining & Technology, C. Duan

"The magnetic separation removal rate of pyrite could be improved effectively by increasing the susceptibility of pyrite. The electromagnetic characteristics and absorption response performance of high-sulfur fine coal were studied in strengthening the susceptibility of pyrite. In the process of treating the sample through the microwave, electromagnetic energy could be converted into heat energy due to dielectric loss and magnetic loss. The RL(dB) was evaluate the performance of absorption response of coal. The microwave improved the susceptibility was in ultra-high frequency region, which is the most natural resonance. The absorption fine coal to microwave was strengthened and microwave energy was improved by adding the magnetite powder with double loss characteristics as the microwave absorber. The dielectric properties and permeability characteristics of the fine coal trend were investigated by maxing magnetite powder. The microwave absorption in different coal thickness was surveyed through the reflection of energy loss.INTRODUCTIONMicrowave desulfurization is one of the most important research directions (Haque, 1999; Makul, Rattanadecho, & Agrawal, 2014; Su, Tang, Zhang, Jing, & Bai, 2014). The working principle of microwave absorption response can be briefly described as the interaction of the sample with microwave energy, which will result in the microwave energy converting into heat energy loss (Keangin & Rattanadecho, 2013). For specific samples, the polarization effect includes multiple polarization mechanisms(Meikap, Purohit, & Mahadevan, 2005). Different polarization mechanisms have different occurrence time and dominant mechanisms. Meantime, energy consumption will be occurred during the process of polarization effect (Chelgani & Jorjani, 2011; Rowson & Rice, 1990) . The absorption of microwave energy in the fine coal is a process of electromagnetic response (Znamenácková, Lovás, Mockovciaková, Jakabský, & Briancin, 2005). Microwave transfers the electromagnetic waves into the heat energy by microwave dielectric loss and magnetic loss for achieving the absorption of microwave energy in the treatment of samples (Lee, Kim, Kim, Chung, & Kim, 2004). The additive magnetic medium is Fe3O4 belonging to microwave energy absorber of double loss medium (Uslu, Atalay, & Arol, 2003)."

Jan 1, 2016

By Z. S. Shao, X. Z. Li

"Sub-critical crack growth plays an important role in long-term creep failure in brittle rock. Based on micromechanics established by using relationship between micromechanical wing crack growth model and macroscopic strain, and comparing theoretical model with testing results, a method, which applies the theory to real rock, is suggested in this paper. Using this method, properties of creep, damage and progressive failure in brittle rock are investigated. Effects of stress state on creep failure time and steady-state creep rate are analyzed and graphically presented. The results are helpful to support structure design and service life evaluation of underground structures with high geostatic stresses. INTRODUCTIONDuring the long-term operation in underground space with brittle surrounding rock, due to chemical action between pore water and rock, the failure of rock often occurs at stresses below its short-term failure strength, which brings serious effect on the long-term stability of underground structure. Thus, the long-term strength of brittle rock attracted wide interests of scholars around the world. The static fatigue limit was predicted by exponential function that is derived from abundant experiment data of stress level and failure time(Schmidtke & Lajtai, 1985), and similar result by relationship between stress state and failure time was also suggested (Lau & Chandler, 2004; Aubertin et al., 2000; Sangha & Dhir, 1972). According to relationship between steady creep rate and stress state during creep, a critical stress that transforms steady-state creep to accelerated creep was studied and the long-term strength was suggested (Tsai et al., 2008; Ma & Daemen, 2006; Lajtai et al., 1991). Based on the results of experiment in compression, the long-term strength of rock was defined by stress at volume strain reversal. When applied stresses are larger than the long-term strength, the microcracks in the rock will grow constantly, damage of rock will increase and failure of rock will occur finally (Chandler, 2013; Bieniawski, 1967; Brace et al., 1966)."

Jan 1, 2015

By J. Lui

At its Copper Cliff Smelter, bulk nickel and copper concentrate is processed in two Inca flash furnaces and Peirce Smith converters to produce Bessemer matte containing 0.6%Fe. After slow cooling and Matte Separation, Bessemer matte is converted into three main products using magnetic separation and flotation technology: (1) a nickel containing chalcocite concentrate (MK); (2) two types of copper containing nickel sulfide (ME and MR); (3) metallics (MYN). MK is further processed in the Inca top blowing bottom stirring MK Reactor to produce semi-blister copper containing ~4%Ni and ~3±1 %S. The semi-blister copper is then purified in the multi-purpose vessels (MPV) to produce blister copper by reducing Ni, Fe and S content through oxidation. High melting point NiO is formed inside the MPVs. The accumulation of solid NiO and other oxides requires periodic cleaning by adding reductant and furnace matte, a unique process called "washout" at Inca. For many years, the reductant used for the "washout" process has been 15%Si Ferro-silicon. With increasing cost and limited suppliers for 15%FeSi, alternative reductants were pursued. This paper summarizes the development and commercialization of new alternative reductants for MPV "washout".

Jan 1, 2007

By R. T. Saxon

Prior to November 1975 there were several failures of front -wheel spindles on large haulage truck s in B.C., attributed to fatigue cracks. Since that time, a non-destructive test program has succeeded in detecting the cracks before catastrophic failure, However, the author regards the failures as just one example of a. general unreliability in large high-strength steel castings and urges the industry to look to forgings for sensitive components of heavy equipment.

Jan 1, 1977

"Dry crushing trials at pilot scale have shown that the IMPTEC Super-fine Crusher has the capacity to generate ultra-fine products from hard mineral assemblages presenting at either coarse or fine feed sizes. The super-fine crusher was introduced at the 27th International Mineral Processing Congress in Santiago Chile, with results from a range of duties, which demonstrated the crusher’s potentially expansive operating scope. This paper focuses on current preparations to progress the technology from pilot scale to commercial scale within a concrete production plant, where lead blast furnace slag will be crushed to ultrafine sizes to generate an active silica product for use as a supplementary cementitious material, which can replace Ordinary Portland Cement. A key objective of the operation is to demonstrate an economical route to reducing the cost of concrete production, improving concrete quality and reducing greenhouse gas emissions. The paper also highlights the potentially key contribution super-fine crushing can make to the long-term viability of iron ore beneficiation by simplifying comminution flow-sheets and reducing operating costs. There is every indication that the technology has the potential to feature universally in metalliferous and industrial mineral flow-sheets. INTRODUCTIONToday’s IMPTEC super-fine crusher is the successful end product of development work over 19 years and is the third particle size reduction device conceived, built and tested over that time. The concept evolved as engineering design progressively developed a mechanism capable of harnessing a highly efficient combination of fundamental particle breakage mechanisms. Early development trials at pilot scale indicated that super-fine crushing had the potential to establish a wet or dry, media free, low energy route to ultra- fine products from hard mineral assemblages. Having achieved some impressive results from open circuit pilot tests on fly ash and granulated blast furnace slag it became clear that the cement industry may well provide opportunities to apply the technology commercially. Following expressions of interest from local cement and concrete plant operators, IMPTEC negotiated an agreement to undertake commercial trials with a SFC 350 super-fine crusher installed on site at a concrete supply plant in South Australia. Super-fine crushing scope was recently expanded following further expressions of interest from research groups involved in the processing of iron ores. Pilot trials are progressing in these areas."

Jan 1, 2016

By Graham Farquharson, Jame Marshall

"Mining towns have always been an important part of Canadian geography. Many Canadians grew up in them. The frontiers of northern Canada would be a lot closer to the United States border but for the pioneering of new mines, new towns, and new transportation routes. Names such as Labrador City, Chibougamau, Val d’Or, Rouyn-Noranda, Kirkland Lake, Timmins, Sudbury, Red Lake, Thompson, Flin Flon, Yellowknife, Whitehorse,Trail and Kimberley are some of the better known larger communities that have grown to become major commercial and government centres, but which started as the base for a mining development.Many other smaller towns never grew beyond being small communities, dependent upon the local mine and many of these are still alive, but perhaps not quite what they used to be. In this list would be Buchans, Schefferville, Chapais, Cadillac, Virginia town, Lynn Lake, Uranium City, Pine Point, and Keno Hill.Nevertheless, all these towns and dozens more like them were residential communities where people lived and raised families and were quite accustomed to being days from the major centres of Montreal, Toronto, Edmonton and Vancouver, and not just hours away as wet end to measure travelling time today."

Jan 1, 1996

By Z. Huda

The effect of various percentages of cold-working and recrystallization on the microstructure and hardness of commercially-pure aluminum plate, has been studied. The 'A critical deformation for the aluminum, has been determined. Experimentation involved cold rolling and recrystallization processes followed by quantitative metallographic practice and the hardness measurements. The raw material chosen was a plate of commercial aluminum which was cold rolled to different percentage of cold-work and then recrystallized by heat treatment at 150°C. The critical deformation percentage of aluminum was computed to be around 30% of cold-worked.

Jan 1, 2007

By John A. C. Fortescue

There is a need for better communication between scientists who plan and carry out mineral exploration research in glacial terrain and the exploration geologists who look for mines. In this paper, four ways in which workshops could be used to close this communication gap are described and discussed in relation to the solution of this problem in Canada.

Jan 1, 1973

By W J. Riva

This paper reviews the circumstances that led to the development and construction of a commercial-scale vertical shaft carbonizer at Conmore, Alberta. This form coking process may be regarded as having potential application in other areas. Coal pelletizing offers a promising method of decreasing coal agglomeration costs under certain circumstances. Pellets can be rolled easily from -35-mesh coal, provided that a minimum of -200-mesh coal is present. Bentonite was found to be the best binder and was most effective when added in amounts of about 2 per cent. The water content of the coal pellets was observed to vary from 18 to 23 per cent. As a by-product of this investigation, it seems possible that fine coal could be converted into stoker feed by this process. A short investigation of the effect of heating rate on the carbonization of pellets was conducted. The low maximum heating rates in certain temperature ranges, necessary to avoid crack formation in the pellets as reported by other

Jan 1, 1964

By L. Tafaghodi, S. Sarbishei

"Following the depletion of nickel sulfide ores, laterites are considered as one of the main sources for producing nickel and cobalt. One of the primary steps in pyrometallurgical extraction of nickel from laterites involves partial reduction of the ore at temperatures below 1000°C. Studying the kinetics of laterite reduction provides valuable information on reducibility of nickel laterites using coal as a reductant. The present study investigates the reduction behavior of a nickel laterite by thermal gravimetric analysis and differential scanning calorimetry. Non-isothermal reduction tests and X-ray diffraction analysis were performed to find the main reactions that occur during the process. The kinetic parameters were calculated by Coats-Redfern method. The general model of simple reaction f(a)=(1-a)n was used for calculating kinetic parameters.INTRODUCTION Nickel (Ni) naturally occurs in the form of sulfide and laterite ores. Laterite ores are mainly available in tropical regions. Weathering phenomena during millions of years has led to the formation of several layers with specific mineralogy (Butt & Cluzel, 2013). The three main layers downward are limonite, smectite, and saprolite (Crundwell et al., 2011). Although laterites are the most available nickel ore resource (70%), their share in the overall Ni production is limited to 40% (Crundwell et al., 2011). The main reasons for not materializing the full potential of laterites are as follows (Ray et al., 1985): •,Laterite ores contain high water content (free and combined) which in turn results in high energy consumption of the extraction process. •,As Ni is present in the form of solid solution in laterites, physical upgrading methods such as flotation are not effective in increasing the Ni content before the extraction process. •,Extracting Ni from sulfide ores involve exothermic reactions which are beneficial due to decreasing the overall energy requirement of the process, however there is not efficient release of energy in the process of extracting Ni from laterite ores."

Jan 1, 2017

By Yujing Jiang, Xuezhen Wu, Bo Li, Tomomi Iura, Gang Wang

"Yielding bolt has been widely used for rock reinforcement in mining and civil engineering in high stress conditions. However, the interaction mechanism of yielding bolt and matrix mass is still not clear at present, and no analytical model is available to predict its reinforcement effect quantitatively. In this paper, the mainstream yielding rock bolts were reviewed firstly. After that, a coupling model is proposed to account for the interaction between yielding bolt and matrix mass. Based on the plane strain axial symmetry assumption and the incremental theory of plasticity, equilibrium equations and compatibility equations of matrix mass, and also the response of yielding rock bolt are deduced theoretically. The proposed method was programmed in Visual Basic development environment, and a semi-analytical solution for the coupling model is achieved. The reinforcement mechanism of yielding bolt in conventional tunnelling is clearly demonstrated through an illustrative case study. The reinforcement effect of yielding bolt is estimated quantitatively, and the distribution of axial force along the bolt is presented. In addition, the validity of proposed method is verified by numerical simulations. INTRODUCTIONHigh stress in surrounding rock mass can cause serious stability problems such as massive squeezing in soft rock and rock burst in hard rock. It is observed that many conventional rock bolts failed when experiencing large displacement, which implies that they are too stiff to sustain large deformation and dynamic conditions (Stillborg, 1994; Hoek et al., 1995). Yielding bolt, which can also be called energy-absorbing bolt, has been widely used for rock reinforcement in mining and civil engineering for these conditions (Neugebauer, E., 2008). This paper focuses on the static reinforcement effects of the yielding bolts with analytical method and numerical simulations."

Jan 1, 2015

By Lawrence Devon Smith

"What is Due Diligence?Within the mining industry the term “due diligence” is used to describe a detailed data review, generally in connection with the purchase or sale of a mineral property, the approval of a large capital expenditure, or the borrowing of a large sum of money.The term originates in the requirement of the board of directors of a corporation to “act honestly and in good faith ... and exercise the care, diligence, and skill that a reasonably prudent person would exercise in comparable circumstances” (OBCA, 1994). Furthermore, the law assumes that a corporation (or its board) will have exercised due diligence in the acquisition of an asset and, therefore, knowingly (in the absence of fraud or deceit) will have taken on the liabilities and obligations associated with the asset (Nelson, 1994). This is the familiar “Buyer Beware”.Directors are liable for their decisions except “if the director relies in good faith upon financial statements of the corporation represented … by an officer of the corporation or in a written report of the auditor, or a report of a lawyer, accountant, engineer, appraiser, or other person whose profession lends credibility to a statement made by any such person.” (OBCA, 1994).Hence the importance of reports prepared by professionals. They provide confirmation that the directors have exercised due diligence in the performance of their duties. For this reason these reports are referred to as due diligence studies"

Jan 1, 1997

By Lawrence Devon Smith

"Within the mining industry the term “due diligence” is used to describe a detailed data review, generally in connection with the purchase or sale of a mineral property, the approval of a large capital expenditure, or the borrowing of a large sum of money.The term originates in the requirement of the board of directors of a corporation to “act honestly and in good faith and exercise the care, diligence, and skill that a reasonably prudent person would exercise in comparable circumstances” (OBCA, 1994). Furthermore, the law assumes that a corporation (or its board) will have exercised due diligence in the acquisition of an asset and, therefore, knowingly (in the absence of fraud or deceit) will have taken on the liabilities and obligations associated with the asset (Nelson, 1994). This is the familiar “Buyer Beware”.Directors are liable for their decisions except “if the director relies in good faith up on financial statements of the corporation represented by an officer of the corporation or in a written report of the auditor, or a report of a lawyer, accountant, engineer, appraiser, or other person whose profession lends credibility to a statement made by any such person.”(OBCA, 1994).Hence the importance of reports prepared by professionals. They provide confirmation that the directors have exercised due diligence in the performance of their duties. For this reason these reports are referred to as due diligence studies."

Jan 1, 1996

By R. E. Evans

This paper contains an analysis of the geography and geology of the Black Lake area, Eastern Townships of Quebec, an outline of the work to be performed, an explanation of the design concept and how it was developed, and a discussion of the actual stripping operation, including details of the machinery being used, etc.

Jan 1, 1967

By W. E. Halle, G. J. S. Govett

"The Institute of Applied Geology, Manila, Philippines, is jointly sponsored by the University of the Philippines, the Philippines Bureau of Mines and the United Nations Development Programme (Special Fund). It provides, in its fourth year of operation, an interesting example of international cooperation in mineral development. Objectives include: (1) the training of mining engineers in modern techniques of mineral exploration; (2) assisting government and industry in discovering new ore deposits; and (3) providing the basis for the establishment of an economically oriented graduate school of geology at the University, the first of its kind in the country. Training of engineers requires roughly one full year, which is divided between academic study and actual field practice. Lecture and laboratory instruction include courses at university level designed specifically to up-grade those aspects of the geological sciences that are required by mining engineers now qualifying as mineral exploration engineers-economic geology, applied geochemistry, geo-physical exploration, petrology and structural geology. The field training involves direct participation in actual mineral exploration projects arranged with the co-operation of the Bureau of Mines and private interests engaged in mineral development and production. The system works well in practice, and the Institute staff and trainees were responsible for outlining new evidence of economic mineralization. It is also apparent from the application of the exploration methods available to the project -geological mapping, air photo interpretation, magnetic, electric, electromagnetic, self potential and gravity surveying as well as geochemical prospecting -that, under the humid, tropical, mountainous conditions in which the practical program was conducted, air-supported geochemical prospecting with attendant reconnaissance geological mapping affords the most economical and effective approach to mineral exploration for at least some of the deposits characteristic of the region."

Jan 1, 1968

By T. S. Smith

INTRODUCTION IN PREPARING this paper for the District 4 Meeting, three factors had to be considered. First, the paper must fit the time alloted; second, it must give a general picture of the geology for those unfamiliar with the property; and third, it must contain some new material in order to be of interest to local delegates. The most comprehensive extant discussion of the geology of the property of McKenzie Red Lake Gold Mines, Limited, is contained in Horwood's report on the general Red Lake area ( 1). This report is the 'bible' of the area, and a general paper on the geology of this particular mine would almost certainly appear to be a condensation of it. It was thought, therefore, that the most suitable procedure would be to base the general outline on Horwood' s report, to extend that outline where possible from information gained since its publication, and finally to leave dangling for the contemplative geologist some of the ideas and problems which ?are currently under consideration. LOCATION AND HISTORY The property of McKenzie Red Lake Gold Mines, Limited, is in Dome township, in the Red Lake mining division of northwestern Ontario. The mine is on McKenzie Island, about four miles north, by water, of the Hasaga mine and old Howey mine.

Jan 1, 1951

By F. Rivard, M. G. Drouet, W. S. Ruff, P. Carabin

"In both the hot rotary-salt-furnace (RSF) treatment of aluminum dross and the cold ball-millsieving (BMS) treatment of zinc dross, enormous amounts of energy and recoverable metal are wasted and large amounts of greenhouse gas are produced. Such wastes and the environment pollution could be avoided by using the DROSRITE PLUS™ technology. Economic and GHG production comparisons between the presently used industrial treatment processes and DROSRITE PLUS™, supported by over one hundred tests conducted in Canada, the US and Europe, are presented. The savings, with DROSRITE PLUS™, would be about $191 and $418 per MT of aluminum and zinc dross, respectively.INTRODUCTIONDross is a material, which forms on the surface of molten non-ferrous metal, such as aluminum or zinc, during melting, metal holding and handling operations when the molten metal is in contact with a reactive atmosphere. Dross normally consists of metal oxides entraining a considerable quantity of molten free (unreacted) metal, and for economic reasons it is desirable to extract the free metal before discarding the residue. In the case of aluminum dross, recovery of the metal is usually carried out by treating the dross in a furnace at a high temperature (Peterson et al., 2002). By contrast, cold zinc dross is crushed in a ball mill followed by sieving to separate the coarse metal portion from the fine oxide residue.The conventional aluminum dross treatment process, using gas or oil-heated rotary salt furnaces (RSF), is thermally inefficient and environmentally unacceptable because of the salt slag and CO2 produced from the combustion of fossil fuels. In the past several years, a number of salt-free processes have been developed and some of these have found limited commercial use (Gripenberg et al., 1994; Lavoie et al., 1990). In all these dross treatment processes, heating of the cold dross in a rotary furnace requires an external energy input that varies between 375 and 2,500 kWh per (metric) tonne of dross. Molten metal separated during processing of the heated dross is tapped, and the remaining solid residue is discharged from the furnace."

Jan 1, 2012

By Iain Sommerville, Hugh Mountford, Dawid D. Smith, Claude Dube, Brett Hixson

JW Aluminum use lean and Six Sigma techniques to continuously improve their target of reliable, repeatable and reproducible (3R) manufacturing. Six Sigma’s second stage gate, known as "Measure" involves identification and qualifying appropriate measuring systems. Metal quality (inclusions) are known in the industry to be an important element in 3R casting. The measurement of inclusions at JW Aluminum historically depended on outside vendors. In order to establish real time inclusion measurement ability within JW Aluminum, inclusion measurement systems in the marketplace were investigated. The qualification of a MetalVision MV20/20 ultrasonic inclusion analyzer are discussed as well as the subsequent application of the system in melting and casting improvement projects.

Jan 1, 2015

By R. A. Parra, Fuentes, C. Godoy, L. E. Arias, C. A. Toro, M. Marin, E. Balladares, V. Parra, G. Reyes, S. N. Torres, D. Sbarbaro

In this paper, we report on the detection of spectral molecular emission of iron oxide (FeO) and copper oxide (CuxO) emitted by reactions occurring in a laboratory scale flash smelting process of pyrite (FeS2) as well as copper concentrate. The novelty of the technique is that, the molecular spectral emission sensing is achieved by using a low spectral resolution and low sensitive radiometer, enhanced with signal processing and matrix factorization techniques. The method was validated using a highly sensitive spectrometer, with a high spectral resolution; achieving a similar FeO spectral pattern as the one obtained after signal processing techniques over low resolution spectral signals. INTRODUCTION Visible-near infrared (VIS-NIR) spectroscopy is an optical contactless sensing technique commonly used to capture information about the emitted, absorbed, transmitted or scattered radiation in a physical or chemical process, with the presence or absence of an excitation light source such as a laser or a broad spectral band source. These techniques coupled with signal processing and machine learning algorithms, sometimes referred as chemometrics (Pisapia et al., 2018), can be found in processes such as: pharmaceutical (Kandpal et al., 2016); food (Coelho et al., 2016); combustion (Ballester & García-Armingol, 2010); siderurgy (Strakowski et al., 2014) industry, among others. In the extractive copper industry there are several technological developments using optical sensing techniques aimed to retrieve information about copper ore and concentrate mineralogical composition such as X-Ray Fluorescence, Qemscan® (Quantitative Evaluation of Minerals by Scanning Electron Microscopy) and X Ray Diffraction (XRD) analysis, however, because of the manual procedures to analyze the samples with these laboratory instrumentation, only discrete information during a daily based operation can be retrieved, making impossible for the operators to take decisions over the involved processes in real time. The aim of our research work presented here is to contribute with sensing and data analysis procedures based on VIS-NIR spectroscopy for the flash smelting process characterization, particularly in this paper, with the detection of FeO and CuxO molecular emissions in a laboratory scale setup.

Jan 1, 2019

By R. A. Lunceford, K. C. Shaver

Acquired by Teck Corporation in 1990, the White Earth project, located in southwestern Colorado is the largest titanium resource in the U.S. Teck Corporation has conducted geologic, reserve, mineral processing, pre-marketing, and environmental baseline studies directed toward the economic feasibility of producing titanium pigment. The White Earth project is situated in a 31 km2 alkalic-carbonatite complex intruded into Precambrian granite and metamorphic rocks about 570 million years ago. Perovskite occurs in a 8 km by 1.2 km Acquired by Teck Corporation in 1990, the White Earth project, located in southwestern Colorado is the largest titanium resource in the U.S. Teck Corporation has conducted geologic, reserve, mineral processing, pre-marketing, and environmental baseline studies directed toward the economic feasibility of producing titanium pigment. The White Earth project is situated in a 31 km2 alkalic-carbonatite complex intruded into Precambrian granite and metamorphic rocks about 570 million years ago. Perovskite occurs in a 8 km by 1.2 km

Jan 1, 1998